Re: mount loop devices not works in schroot

[Jan Kiszka <jan.kiszka@siemens.com>]

On 18.01.24 08:16, Srinuvasan Arjunan wrote:
> Hi All,
> 
>              Presently we migrated the chroot to sbuildchroot and one of
> my image creation part i try to mount some temporary file system as a
> loop device and do create volumes and other stuffs.
> 
> Here i could see am not able to mount the file system as a loop device
> specifically in chroot.
> 
> reproduce steps:
>  
> 1. chroot into the created session 
> 2. dd if=/dev/zero of=ext4.img bs=4k count=2048
> 3.mkfs.ext4 ext4.img
> 4. mnt=$(mktemp -d)
> 5.  mount -o loop 'ext4.img' "${mnt}"
> 
> when i mount this ext4.img as a loop devices it throws the below error:
> Error: "mount: /tmp/tmp.7oJoEpL0vt: mount failed: Operation not permitted." 
> 
> But the above steps are working fine in my host machine.
> 
> I hope we need to install the loop module in chroot or any other
> suggestion that would be helpful to mount loop devices in schroot sessions.
> 
> Note:  losetup also not works in schroot.
> 

I don't think you can run such stuff in the schroot, and you will surely
not be able to once we fully de-privilege the build. That's why I
suggested to you already to get rid of this loop-mount requirement.

Jan

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